Snapshot A 17-year-old female presents complaining of an irresistible urge to sleep at sudden times throughout the day. This has disturbed her school functioning. She sometimes feels like she "is paralyzed" for several minutes when she wakes up. She "passed out" one day at school when she was startled by her boyfriend. Introduction Clinical definition disordered regulation of sleep cycles nocturnal and narcoleptic sleep episodes start off with REM sleep patients cannot avoid falling asleep Epidemiology Strong genetic component Typically onsets in young adulthood ETIOLOGY Pathophysiology hypocretin deficiency in lateral hypothalamus (per DSM-V) Presentation Symptoms excessive daytime sleepiness naps can be refreshing may include hallucinations hypnagogic just before sleep hypnopompic just before awakening cataplexy loss of all muscle tone following a strong emotional stimulus only some patients sleep paralysis short paralysis with awakening STUDIES Polysomnography Treatment Pharmacologic modafinil is first line other stimulants e.g., methyphenidate (Ritalin), amphetamines may be limited by their adverse effects such as hypertension and anorexia TCAs (e.g., clomipramine) if severe cataplexy is present may be limited by their anticholinergic effects Sleep regulation scheduled daily naps avoid sleep deprivation or long naps